1. Field of the Invention
The present application relates to crystalline forms of topotecan hydrochloride and processes for making the same.
2. Description of the Related Art
Topotecan hydrochloride is (10-[(dimethyl amino)methyl]-4-ethyl-4,9-dihydroxy-1H-pyrano[3′,4′:6,7]indolizino[1,2-b]quinol-ine-3,14(4H,12H)dione hydrochloride) a compound of formula (I)

U.S. Pat. No. 5,004,758 discloses water soluble camptothecin analogs, which includes topotecan (9-dimethylamino methyl-10-hydroxy camptothecin), preferably (S)-topotecan and its hydrochloride salt.
PCT Application No. WO2005/046608 discloses a crystalline form of topotecan monohydrochloride pentahydrate with an X-ray diffraction pattern depicted in FIG. 1 therein. For the purpose of the present disclosure, this crystalline form is designated Form A.